Function NoMoisSemaineIso(Nsemaine As Byte, An As Integer)
Dim J1 As Date, LundiSem1 As Date
J1 = DateSerial(An, 1, 1) '1er de l'an
LundiSem1 = J1 - Weekday(J1, 2) + IIf(Weekday(J1, 2) <= 4, 1, 8)
NoMoisSemaineIso = Month(LundiSem1 + 7 * Nsemaine - 7)
End Function